The role of this Core is to provide coordinated services for experiments in the component Projects requiring the use of lasers for photochemical generation of ROS, as well as the use of microscopy and flow cytometry facilities for cell analysis following ROS generation. The Core will perform two major functions. First is a service function for routine wide field and confocal microscopy, flow cytometry, and laser irradiation that involve the use of standard shared instrumentation. In this role the Core will provide rapid access with trained personnel who will assist project investigators in data acquisition and analysis. The second major function of the Core is to develop specialized techniques, such as evanescent optical wave irradiation, laser microbeam irradiation, time-resolved microscopy, and two photon microscopy, that are specifically designed and optimized for an individual project's needs. This latter aspect of the Core takes advantage of the unique capabilities in optical technology development that exist within the Wellman Labs and provides the flexibility to implement additional features in the optical systems as the projects evolve. The Core personnel will work closely with project investigators to ensure that state-of-the-art instrumentation is available and utilized in the most optimal way for individual research projects.